1. Field of the Invention
The present invention relates to a working vehicle in which a muffler reducing engine exhaust sound is arranged at a rear portion of a traveling vehicle body.
2. Description of Related Art
As a working vehicle configured as described above, Related Art 1 discloses a configuration in which a drive unit, in which an engine and a transmission case is connected, is arranged at a rear position of a traveling vehicle body, and a muffler is arranged at a position above the drive unit and below a cargo bed. The muffler has a cylindrical shape and is arranged in an orientation having an axis of the cylindrical shape in a longitudinal direction. The muffler is configured in a manner that an exhaust gas of an engine is supplied to a front end of the muffler and the exhaust gas is discharged from a rear end of the muffler.
Related Art 2 discloses a configuration in which a drive unit configured by an engine and a transmission case is arranged at a rear position of a traveling vehicle body, and, in this working vehicle, a pair of left and right long longitudinal frames that constitute a vehicle main frame are arranged at rear positions of the traveling vehicle body, and the drive unit is arranged in a space surrounded by the pair of left and right long frames in a plan view.
Related Art 2 discloses a configuration in which a muffler having a cylindrical shape and having an axis of the cylindrical shape in the longitudinal direction is arranged at a position parallel to the engine and on a more inner side than the pair of left and right long frames. The muffler is configured in such a manner that an exhaust gas of the engine is supplied from a front end and discharged from a rear end.    [Related Art 1] Japanese Patent Laid-Open Publication No. 2010-190152    [Related Art 2] Japanese Patent Laid-Open Publication No. 2009-67144
As in the utility vehicle disclosed in Related Art 1, in a working vehicle in which a drive unit including an engine and a transmission case is arranged at a rear position of a traveling vehicle body and rear wheels are arranged at two sides of the drive unit, in order to secure a space for arranging the rear wheels, a space for accommodating the drive unit is limited, and thus, a muffler is to be arranged in a limited space.
Further, in a configuration in which a working vehicle is provided with a continuously variable transmission, a space accommodating a drive unit is further narrowed. Therefore, arrangement for a muffler is likely to be difficult, and thus there is room for improvement. In order to avoid such a disadvantage, it is also possible to enlarge a dimension in a vertical direction of the space where the drive unit is arranged. However, in this case where the dimension in the vertical direction is enlarged, a cargo bed arranged above the drive unit is at a high level, and the center of gravity of the traveling vehicle body also rises, and thus, there is room for improvement.
A purpose of the present invention is to reasonably configure a working vehicle in which a muffler is arranged in a limited space without wastefully enlarging a space where a speed change unit is arranged.
As in the working vehicle disclosed in Related Art 2, in a working vehicle in which a drive unit including an engine and a transmission case is arranged at a rear position of a traveling vehicle body and rear wheels are arranged at two sides of the drive unit, in order to secure a space for arranging the rear wheels, a space accommodating the drive unit is limited, and thus, a muffler is to be arranged in such a limited space.
Further, as in the working vehicle disclosed in Related Art 2, in a working vehicle in which longitudinal long frames for supporting an engine and a transmission case are provided, it is necessary to consider positional relationship with the frames to arrange a muffler. It is also possible to displace the frames upward and in a lateral direction in order to arrange the muffler. However, in this case where the frames are displaced, the traveling vehicle body becomes larger, and thus, there is room for improvement.
Another purpose of the present invention is to configure a working vehicle in which a muffler is arranged in a limited space by reasonably utilizing arrangement of frames.